The PM himself has explained.
http://www.straitstimes.com/news/singapore/transport/story/steady-progress-reducing-train-downtime-and-malfunctions-despite-rece But I disagree with 2 of his points: "Maintaining and building our public transport system is a tough, high pressure job. Every night after trains stop running, the maintenance and repair crews have only a few hours to maintain the tracks and trains, to get them ready for another day of service." Nobody is debating whether it is a "tough, high pressure" job or not. Some countries run their subways even longer hours than ours. Are they not tough also? And we've had the MRT since 1987, earlier than some of us were even born. It's not a new system and I wonder why that "few hours" the maintenance crew have seemed to only impact in recent years when the trains broke down more frequently. "Unfortunately we've had a series of incidents recently, but we are making steady progress." How does the increasing string of MRT delays and breakdowns constitute "steady progress"? It's like telling a student who gets continually worse grades of C, D, and F for exams: "Don't worry, you are making steady progress!"